Various processes for the production of synthetic fatty acids are well known in the art. U.S. Pat. No. 2,384,817 describes the alkaline oxidation of an alcohol. This process requires a stoichiometric amount of alkali and hence a stoichiometric amount of acid.
British Pat. No. 849,951 discloses the oxidation of paraffin process which gives low quality fatty acids with poor color, odor and high peroxide and carbonyl content.
In the process which oxidizes an .alpha.-olefin as described in U.S. Pat. No. 3,692,810, a fatty acid of one less carbon atom than the starting material is obtained. Various types of by-products including carbon dioxide, formic acid, formaldehyde, other aldehydes, keto compounds, dibasic acids and polymers are also produced.
In the carboxylation of .alpha.-olefins as described in U.S. Pat. No. 3,819,669 considerable amounts of undesirable branched chain fatty acids are also produced.
Ziegler technology as described in U.S. Pat. No. 3,244,735 is used only for the production of even numbered carbon atom fatty acids and the yield of fatty acids is low.
Telomerization of ethylene described in U.S. Pat. No. 3,637,478 gives a wide range of odd number carbon atom fatty acids including C.sub.3, C.sub.5, C.sub.7, C.sub.9, C.sub.11, and C.sub.13 fatty acids.
At the present time there is no known prior art which describes the cross dimerization of 1,3-butadiene with methyl-2,4-pentadienoate to prepare the unsaturated linear dimers methyl nonadienoate and methyl nonatrienoate which may be hydrogenated to methyl pelargonate and hydrolyzed to pelargonic acid.
The Emery Process of ozonolysis of oleic acid results in the formation of a one-to-one ratio of azealaic and pelargonic acid.
The present invention is based on the discovery that methyl nonadienoate and methyl nonatrienoate monoesters can be prepared via a palladium (II)/tertiary phosphine complex catalyzed linear dimerization of methyl-2,4-pentadienoate with butadiene which monoesters may be converted by catalytic hydrogenation and subsequent hydrolysis to methyl pelargonate (methyl nonanoate) and pelargonic acid respectively.